Matthew McConaughey had some tough love for aspiring actors at the Film Society of Lincoln Center’s screening of his latest — “The Exorcist” director William Friedkin’s “Killer Joe” — Tuesday. When one audience member asked for a tip, McConaughey recalled advice given to him by “A Time to Kill” director Joel Schumacher: “There are no ‘Help Wanted’ signs in Hollywood. And the guards of the gate are not there to keep you in.” Co-star Gina Gershon also made the Film Comment Selects screening, and the pair further promoted the movie at a Cinema Society and Bally event at No. 8, where guests included Carla Gugino, Graham Nash and Friedkin’s wife, former Paramount CEO Sherry Lansing.